Re: [net-next 11/13] igb: Make Tx budget for NAPI user adjustable

Stephen Hemminger
2011-09-28T15:12:04Z

On Wed, 28 Sep 2011 07:00:55 -0400
Neil Horman <nhorman@tuxdriver.com> wrote:

> I was thinking of something along the lines of two more attributes in
> /sys/class/net/<if>/queues:
> napi_weight
> irq
>
> The former is the napi weight of a given napi instance associated with a queue,
> while the latter is a symlink either to ../device/irq or ../device/msi_irqs/<n>/
> (or perhaps to ../devices/msi_irqs/<n>/irq if we want more consistency). This
> lets us tune the napi weight of a queue and know what interrupt is associated
> with it. That seems fairly sane to me.

This breaks for the case of some corner case devices like multi-port Marvell boards.
There can be a N to 1 or 1 to N relationship between NAPI and the device.